Automated product profiling apparatus and product slicing system using same

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. Ser. No. 11/100,720, filed Apr. 7, 2005, now U.S. Pat. No. 7,450,247 which is a continuation of U.S. Ser. No. 09/959,876, filed Feb. 19, 2002, now U.S. Pat. No. 6,882,434 which is a national stage application of PCT/US00/10691, filed Apr. 20, 2000, which claims priority from U.S. Provisional Application No. 60/130,208, filed Apr. 20, 1999.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not Applicable

BACKGROUND OF THE INVENTION

The present invention relates to an apparatus for determining the profile of a product that is to undergo a subsequent physical process. The subsequent physical process is one in which the product profile is needed to insure proper processing of the product.

In the particular embodiment disclosed herein, the specific subsequent physical process includes slicing the product into individual slices on a slicing machine. Such slicing machines are principally, but not exclusively, used for slicing food products such as cheese, meat and pressed or molded meat products.

Typically such slicing machines include a rotating blade and a product feeder that drives the product forward towards the blade so that successive slices are cut from one face of the product. The distance through which the product is advanced between successive cuts of the blade determines the thickness of the slices. Where the product is of uniform shape and density, it may be sufficient to use a single predetermined slice thickness to give a slice or group of slices of the required weight. Further, it may be sufficient to provide an output scale proximate the output side of the blade to measure the current weight of the slice to product and adjust the thickness of the subsequent slice(s) to make the desired unit weight.

In general, however, variations in the shape and density of the product mean that the weight of a slice of a given thickness varies. A previous approach to dealing with this variation is described and claimed in U.S. Pat. No. 4,428,263, which is hereby incorporated by reference. That patent describes a process in which an automatic slicing machine is programmed to vary the thickness of the slices in accordance with a typical weight distribution for the product.

It has also been proposed to make some determination of the cross-sectional area of the product as it is cut. One such system is purportedly disclosed in U.S. Pat. No. 5,136,906, titled “Slicing Machine”, and assigned to Thurne Engineering Co., Ltd. According to that patent, a slicing machine for cutting slices from a product includes a camera arranged to view a cut face of the product, boundary recognition apparatus arranged to process image signals from the camera to determine a boundary of the cut face, calculating apparatus arranged to calculate a parameter characteristic of the cut face from image data corresponding to regions of the cut face within the boundary, and control signal generating apparatus arranged to generate a control signal to control the operation of the slicer in accordance with the determined parameter.

Although the foregoing system may be suitable for low-throughput slicing machines, it is significantly less suitable for high-speed slicing machines, such as those available from Formax, Inc., of Mokena, Ill., under the brand name S-180.TM.. First, by calculating the product profile at the cut face, a very limited amount of processing time is available to perform the calculations that are necessary to ensure the proper thickness of each slice before the cut face must again be imaged for processing the thickness of the next slice. Second, substantial measurement inaccuracies may result from shadowing effects resulting from the relative positions of the illumination source, cut face, and slicing machine components—a problem not addressed in the '906 patent. Third, further measurement inaccuracies are introduced by the apparent assumption that the profiles at the bottom and a side of the product are linear. Finally, by attempting to measure the product profile at the cut face, substantial inaccuracies may be introduced due to the presence of scrap product. One of the goals of the apparatus described in the '906 patent is to remove the inaccuracies introduced by the scrap product. However, by addressing this problem at the cut face, the apparatus of the '906 must necessarily introduce a further level and higher degree of image processing.

The present inventors have addressed many of the foregoing problems inherent in the product profiling operations of prior art apparatus. To this end, they have developed an accurate and cost-effective product profiling apparatus that is suitable for use, for example, in connection with high-speed product slicing machines.

BRIEF SUMMARY OF THE INVENTION

An apparatus for acquiring a profile of a product for use in subsequent processing of the product is set forth. The apparatus includes a scanning chamber for accepting the product and one or more product drives that are operable to drive the product through the scanning chamber prior to delivery of the product to a subsequent product processor. The apparatus also includes a vision system disposed to acquire visual information relating to the profile of the product prior to delivery of the product to a subsequent product processor and a control system connected for control of the vision system and operating to convert the information received from the vision system into a format suitable for use by a subsequent product processor.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

<figref idref="DRAWINGS">FIG. 1</figref> is a perspective view of a product processing system constructed in accordance with one embodiment of the present invention.

<figref idref="DRAWINGS">FIG. 2</figref> is a schematic block diagram of one embodiment of a control system that may be used in the profiling apparatus of the system illustrated in <figref idref="DRAWINGS">FIG. 1</figref>.

<figref idref="DRAWINGS">FIG. 3</figref> is an exemplary image obtained by the upper vision system of the embodiment of the profiling apparatus illustrated in <figref idref="DRAWINGS">FIG. 1</figref>.

<figref idref="DRAWINGS">FIGS. 4 and 5</figref> are cross-sectional views of one embodiment of a profiling apparatus that may be used in the system <figref idref="DRAWINGS">FIG. 1</figref>.

<figref idref="DRAWINGS">FIG. 6</figref> is a schematic cross-sectional view showing an input stacker.

<figref idref="DRAWINGS">FIG. 7</figref> is a schematic cross-sectional view showing a product stopper at the inlet to the vision system housing.

DETAILED DESCRIPTION OF THE INVENTION

<figref idref="DRAWINGS">FIG. 1</figref> illustrates a product processing system, shown generally at <b>10</b>, that performs a physical process on a product in which the physical process is dependent on accurate measurement of the profile of the raw product. As shown, product processing system <b>10</b> is comprised of a product profiling apparatus <b>15</b> and a product processor <b>20</b>. The product profiling apparatus <b>15</b> functions to measure the profile of the raw product and provide the profile information to the product processor <b>20</b> that, in turn, uses the information to accurately execute the physical process that is to be performed on the raw product.

In the illustrated embodiment, the acquisition of the product profile information is completed before the particular raw product undergoes physical processing in the product processor <b>20</b>. Using the configuration shown in <figref idref="DRAWINGS">FIG. 1</figref> in which the profiling apparatus <b>15</b> is disposed prior to the product processor <b>20</b>, it is possible to acquire complete product profiles for several individual raw products before each of the raw products is provided to the input of the product processor <b>20</b>. Additionally, if the profiling apparatus <b>15</b> is designed as a stand-alone apparatus, then the profiling apparatus <b>15</b> may be used to provide product profile information to a plurality of different product processors that are operating in either a time sequential or concurrent manner.

Generally stated, the profiling apparatus <b>15</b> is comprised of an input section <b>25</b>, a scanning section <b>30</b>, and an output section <b>35</b>. The input section <b>25</b> includes a plurality of support bars <b>40</b> that are disposed to support the product <b>45</b> that is to be profiled. A plurality of upstanding fingers <b>50</b> extend through interstitial regions between the support bars <b>40</b>. The fingers <b>50</b> engage a rear portion of product <b>45</b> and drive it into the scanning section <b>30</b>. The fingers are arranged to be vertically above the support bars when moved in the driving direction and vertically beneath the bars when conducted in the return direction.

Scanning section <b>30</b> includes a housing <b>55</b> having an input end that is open to receive product <b>45</b> and an outlet end that is open to allow product <b>45</b> to exit therefrom. In the illustrated embodiment, housing <b>55</b> comprises a principal housing portion <b>60</b>, an upper vision system housing <b>65</b>, and a lower vision housing <b>70</b>. The upper vision system housing <b>65</b> includes an upper vision system disposed therein. The upper vision system of the disclosed embodiment includes a vertically directed line laser <b>75</b> for illuminating one side of the product in a fixed plane traversed by the driven product and an associated camera <b>80</b> vertically angled for imaging the laser-illuminated contour of the product <b>45</b>. Similarly, the lower vision system housing <b>70</b> includes a lower vision system disposed therein that is comprised of a line laser <b>85</b> and corresponding camera <b>90</b> for addressing the other side of the product. Each of the upper and lower vision system housings <b>65</b> and <b>70</b> includes an opening that is positioned to allow the respective vision system to view a product <b>45</b> passing through the principal housing <b>60</b>. These openings may merely comprise cut out sections. Preferably, however, the openings are covered with a transparent material to form a window that mechanically isolates the vision system components from the components disposed in the principal housing <b>60</b> yet does not interfere with the vision system operation.

Although, for purposes of this overview description of the product profiling apparatus <b>15</b>, with reference to the early Figures, a single line laser is shown for use in each of the upper and lower vision system housings <b>65</b> and <b>70</b>, it is considered more preferable, as further discussed below with respect to a more detailed discussion of structure and operation of the system machinery, that each of the vision system housings contain two opposing line lasers for illuminating downwardly and across the product from opposed sides of the product. In instances of a considerably uneven profile and/or in the event of highly reflective surface characteristics, opposed sides illumination on the product provides for higher resolution camera imaging.

Within principal housing <b>60</b>, product <b>45</b> is supported by a plurality of rounded support bars <b>95</b>. These support bars <b>95</b> may be formed as extensions of support bars <b>40</b>, or may be formed as a support component that is distinct from support bars <b>40</b>. The number and diameter of the support bars <b>95</b> should be minimized to facilitate accuracy of the scanning measurements provided by the lower vision system. Most preferably, although not shown, the diameters of the support bars <b>95</b> are substantially reduced to a minimum where they cross the laser light line emanating from the lower vision system laser.

Product <b>45</b> is driven through the principal housing <b>60</b> by a product drive, shown generally at <b>100</b>. In the illustrated embodiment, the product drive <b>100</b> is comprised of a product engagement member <b>105</b> that is disposed to engage a rear portion of product <b>45</b> and drive it along support rods <b>95</b> through the principal housing <b>60</b>. Product engagement member <b>105</b> includes a plurality of slots that are disposed to allow concurrent operation of the fingers <b>50</b> and product engagement member <b>105</b> at the input end of the principal housing <b>60</b>. A pair of upstanding members <b>110</b> are connected to opposite ends of the product engagement member <b>105</b>. The upstanding members <b>110</b>, in turn, are fastened to respective drive belts <b>115</b> and <b>120</b> to move the product engagement member <b>105</b> and corresponding product <b>45</b> through the principal housing <b>60</b>. The drive belts <b>115</b> and <b>120</b> are preferably driven at a constant, precise velocity by, for example, a servo motor, a motor with a resolver, etc.

At the outlet end of the principal housing <b>60</b>, the product <b>45</b> is engaged by another set of fingers <b>130</b> that extends through interstitial regions of support bars <b>95</b>. Support bars <b>95</b> may be extended to the output section <b>35</b> or, alternatively, a further distinct set of support bars may be used to support the product <b>45</b> at the output section <b>35</b>. Fingers <b>130</b> engage the rear portion of product <b>45</b> and drive it to the output section <b>35</b> and therefrom to the processing apparatus <b>20</b>, which, in the disclosed embodiment, is a slicing machine.

<figref idref="DRAWINGS">FIG. 2</figref> is a schematic block diagram of one embodiment of a control system suitable for controlled operation of product profiling apparatus <b>15</b>. In the illustrated embodiment, the control system comprises a central controller <b>150</b> that is responsible for 1) controlling the drive mechanisms associated with various portions of the profiling apparatus <b>15</b>; 2) coordinating the operation of the vision systems, including acquisition of the profile data; and 3) communicating the profile data to control systems for one or more product processors <b>20</b>. To this end, the central controller <b>150</b> is connected to receive sensed signals from and provide motion control signals to each of the input and output section drives <b>155</b> and <b>160</b> and the scanning section drive <b>165</b>. Similarly, the central controller <b>150</b> is connected to receive sensed signals from and provide scanning control signals to the upper and lower vision systems <b>170</b> and <b>175</b>. Ultimately, the profile information acquired from the upper and lower vision systems <b>170</b> and <b>175</b> is communicated to the control system <b>180</b> of at least one product processor <b>20</b>. The profile information may be communicated to the control system <b>180</b> in any one of a variety of processing states. For example, the central controller <b>150</b> may communicate raw profile data to the control system <b>180</b>. Alternatively, or in addition, the central controller <b>150</b> may communicate the profile information after the raw data it acquires has been processed at the central controller <b>150</b> thereby relieving the control system <b>180</b> from much of the additional processing overhead associated with profile calculations.

If more than one product processor <b>20</b> is to be served by a single product profiling apparatus <b>15</b>, then a method for tracking each product <b>45</b> through the system to insure that each of the product processors <b>20</b> receives the correct profile data must be provided. For example, each of the products <b>45</b> may be provided with a bar-code or other visual image marker that may be acquired or otherwise input to the central controller <b>150</b> as well as the particular control system <b>180</b>, <b>180</b>′, <b>180</b>″ associated with the particular product processor <b>20</b> that is to slice the particular product. When the identity of the product <b>45</b> that is to be sliced by the product processor is determined by the respective control system <b>180</b>, <b>180</b>′, <b>180</b>″, the particular control system may request the profile data associated with the identified product from the central controller <b>150</b>.

Operation of the product profiling apparatus <b>15</b> can be described with respect to <figref idref="DRAWINGS">FIGS. 1 and 2</figref>. First, the product <b>45</b>, shown here as a slab of bacon or the like, is provided at input section <b>25</b> where it is supported by support rods <b>40</b>. Central controller <b>150</b> then activates input section drive <b>155</b> so that fingers <b>50</b> engage the rear portion of product <b>45</b> and drive it into the scanning section <b>30</b>. Product engagement member <b>105</b> is preferably hinged to swing out of the way or otherwise glide over the upper surface of product <b>45</b> as it is moved through the opening at the input of the scanning section <b>30</b>. The central controller <b>150</b> directs the scanning section drive <b>165</b> to operate so that the product engagement member <b>105</b> contacts the rear portion of product <b>45</b> and begins to drive product <b>45</b> through the interior chamber of the principal housing <b>55</b>. Preferably, the product <b>45</b> is driven a small distance over support rods <b>95</b> before reaching the position in the principal housing <b>55</b> in which product scanning begins. This allows the product to settle upon the support rods <b>95</b> and against product engagement member <b>105</b> before scanning thereby increasing the accuracy of the resulting profile data.

In accordance with one embodiment of the profiling apparatus <b>15</b>, a resolver or the like associated with the scanning section drive <b>165</b> generates control pulses corresponding to incremental movement of the product <b>45</b> over a fixed distance through the principal housing <b>55</b>. These control pulses are used as synchronization signals that the central controller <b>150</b> uses to trigger the acquisition of a profile reading. Here, the profile readings are in the form of a visual image captured by the cameras <b>80</b> and <b>90</b> at fixed increments along the length of the product <b>45</b>. The product profile is accentuated by directing a line of laser light across the upper and lower surfaces of the product <b>45</b>. Accordingly, the interior of the principal housing <b>55</b> should be as dark as possible so that cameras <b>80</b> and <b>90</b> may detect the line projected by line lasers <b>75</b> and <b>85</b>.

<figref idref="DRAWINGS">FIG. 3</figref> is an exemplary image acquired by camera <b>80</b> of profiling apparatus <b>15</b>. Although camera <b>80</b> is capable all of providing an image of 640.times.480 pixels, only a sub-portion of that entire available image is extracted by central controller <b>150</b> for further processing. As shown, the resulting image is comprised of linear end regions <b>200</b>. The linear end regions are formed by reflection of the light from line laser <b>75</b> by a pair of reference reflectors that, preferably, are disposed to be even with the upper surfaces of support rods <b>95</b>. There are a plurality of elevated, non-linear regions between linear regions <b>200</b>. These non-linear regions correspond to the upper profile of product <b>45</b> that has been illuminated by line laser <b>75</b>. By taking measurements of the vertical distance (e.g., the number of vertical pixels) between linear end regions <b>200</b> and the elevated, non-linear regions, it is possible to calculate the contour of the profile of the product at the position along the interior of principal housing <b>55</b> at which the image was acquired. By acquiring a number of such images along the length of product <b>45</b>, an accurate representation of the upper profile of product <b>45</b> can be obtained. Similar images are concurrently acquired by camera <b>90</b> based on illumination of the lower portion of product <b>45</b> by line laser <b>85</b>. As in the case of the upper profile measurements, linear reference regions are formed by reflection of the light from line laser <b>85</b> by a pair of reference reflectors. From the images of the upper and lower product surfaces that are acquired by the upper and lower vision systems <b>170</b> and <b>175</b>, the central controller <b>150</b> can provide a substantially accurate data representation of the complete product profile to control system <b>180</b> of product processor <b>20</b>.

Depending on the content of the product <b>45</b>, the laser light impinging on the upper surface of product <b>45</b> may be dispersed in different manners. For example, if the product <b>45</b> is bacon or another fat-containing comestible, fatted regions, such as at <b>205</b> disperse the laser light to a greater degree than lean regions <b>210</b>. As a result, a broader light band is formed at the fatted regions <b>205</b>. Controller <b>150</b> may compensate for this dispersion by, for example, selecting the area of highest dark pixel concentration for the vertical measurement. Alternatively, a vertical distance measurement may be obtained by taking the average vertical distance of the uppermost vertical distance measurement and the lowermost vertical distance measurement.

As shown in <figref idref="DRAWINGS">FIG. 3</figref>, the light reflected from the surface of product <b>45</b> may be blocked from the view of the camera. These regions appear as void regions <b>215</b>. In such regions, central controller <b>150</b> may be programmed to assume a linear transition of the surface contour. Since void regions <b>215</b> are generally of a very limited dimension, this assumption still provides for an accurate representation of the overall product profile. Similarly, an assumption that there is a linear transition of the surface contour at the regions of the lower surface of product <b>45</b> that are blocked by support rods <b>90</b> does not significantly diminish the accuracy of the profile measurements. To minimize any inaccuracies introduced by the presence of support rods <b>95</b>, the number and diameter of support rods <b>90</b> should be minimized. Further, support rods <b>95</b> should have a generally round cross-section so that they generate obstructed or otherwise unusable regions of the profile image that are substantially equal in the length.

Once product <b>45</b> as been driven to the outlet portion of scanning section <b>30</b>, the central controller <b>150</b> controls the output section drive <b>160</b> so that fingers <b>130</b> engage the rear portion of product <b>45</b> and drive it from the interior of scanning section <b>15</b> to output section <b>35</b>. Product <b>45</b> may be removed by an operator from section <b>35</b> and provided to the input of a subsequent product processor <b>20</b>. Alternatively, the output section <b>35</b> and corresponding output section drive <b>160</b> may be designed to drive product <b>45</b> into a loading position on the subsequent product processor.

Profiling apparatus <b>15</b> may include a digital scale <b>230</b> (shown schematically in <figref idref="DRAWINGS">FIG. 1</figref>) for weighing the product <b>45</b>. The output of the digital scale may be provided to central controller <b>150</b>. Central controller <b>150</b> may be programmed to calculate the overall volume of product <b>45</b> based on the profile measurements. Central controller <b>150</b> may then use the overall product value and the weight provided by the digital scale to calculate the average density of the product <b>45</b>. The average density measurement may be used by a slicing machine, such as product processor <b>20</b>, in combination with the profile measurements to calculate the product slice thicknesses that are required to make a particular weight, such as the weight of product slices that are to be provided in a single consumer package. Alternatively, one or more of the average density, overall volume, or product profile measurements/calculations may be executed by the control system <b>180</b> of the slicing machine.

<figref idref="DRAWINGS">FIGS. 4 and 5</figref> illustrate a specific embodiment of the profiling apparatus <b>15</b> in which like parts are similarly numbered. Of note in connection with the embodiment shown in these Figures are the drive mechanisms associated with input section <b>25</b>, scanning section <b>30</b>, and output section <b>35</b>.

It has been found and is considered preferable that, rather than using a single line laser to illuminate a surface of the product as shown in <figref idref="DRAWINGS">FIG. 4</figref>, a pair of generally opposed lasers applying overlapping beams to cover that surface of the product can yield more profile data and better resolution in the camera image. This would be the case especially in instances where the product surface is quite irregular and/or contains large fatted regions since these situations tend to result in shadowing an/or blurring in the camera image. The more the profile data and the better the resolution in the camera image, the more definite and precise is the surface profile data, there being less need for averaging or extrapolation.

In the case of using more than one line laser in each of the vision system housings above and below the product, the lasers are preferably disposed on opposite sides of the product and projecting their beams down onto and across the product. The camera position generally does not change. In this way, a triangulated approach to capture of the surface profile on both respective sides of the product is utilized.

As illustrated, the drive mechanisms associated with the input section <b>25</b> and output section <b>35</b> are interrelated. More particularly, the drive mechanisms are comprised of a single, dual-ended pneumatic actuator, shown generally at <b>300</b> that is mounted below support rods <b>40</b> (the support rods throughout are continuous and formed as a single set of rods). Actuator <b>300</b> includes a piston rod <b>305</b> having a first end connected to a first finger engagement assembly <b>315</b> and a second end connected to a second finger engagement assembly <b>310</b>. Finger engagement assembly <b>310</b> includes the fingers <b>50</b> thereon while finger engagement assembly <b>315</b> includes the fingers <b>130</b> thereon. Fingers <b>50</b> are disposed on a pivot rod <b>320</b> along with one or more counterbalance mechanisms <b>325</b>. The counterbalance mechanisms <b>325</b> urge fingers <b>50</b> to rotate about a horizontal axis defined by pivot rod <b>320</b> until fingers <b>50</b> engage one or more stop members <b>330</b>. The one or more stop members <b>330</b> are disposed to the stock fell rotation of fingers <b>50</b> when they are in an upright position. This arrangement allows fingers <b>50</b> to slide under a successive product <b>45</b> disposed on the input section <b>25</b> as the fingers are driven back to the home position after delivering a previous product <b>45</b> to the scanning section <b>30</b>.

A similar arrangement is provided for finger assembly <b>315</b> disposed at the first end of piston rod <b>305</b>. Here, however, the one or more counterbalance mechanisms <b>335</b> of the finger assembly <b>315</b> are positioned to engage a further stop member <b>340</b> at the output position of the output section <b>35</b>. As the fingers <b>130</b> drive product <b>45</b> along output section <b>35</b>, counterbalance mechanisms <b>335</b> are driven into engagement with the further stop mechanisms <b>340</b>. This causes the fingers <b>130</b> to rotate about a horizontal axis defined by pivot rod <b>345</b> which assists in driving the product <b>45</b> from output section <b>35</b> to, for example, the input of a slicing machine.

In the embodiment shown in <figref idref="DRAWINGS">FIGS. 4 and 5</figref>, the scanning section drive includes motor <b>350</b> that is connected to rotate drive roller <b>355</b>. Drive roller <b>355</b>, in turn, drives belts <b>115</b> and <b>120</b>, each of which extends between drive roller <b>355</b> and idle roller <b>360</b>. Securement mechanisms <b>365</b> are connected to upstanding members <b>110</b> (shown in <figref idref="DRAWINGS">FIG. 5</figref>) to secure upstanding members <b>110</b> and product engagement member <b>105</b> with drives belts <b>115</b> and <b>120</b>. The securement mechanisms <b>365</b> are connected to one another by a strut <b>372</b> to enhance the rigidity of the overall drive mechanism. Additionally, securement mechanisms <b>365</b> each engage respective guide rods <b>377</b> that extend along the length of the transport path along which the product engagement member <b>105</b> moves product <b>45</b> through scanning section <b>30</b>. Preferably, securement members <b>365</b> each include a pivoted connection <b>378</b> that allows the product engagement member <b>105</b> to glide over the upper surface of a product <b>45</b> disposed in the scanning section <b>30</b> as member <b>105</b> is returned to its home position after driving a product from the scanning section <b>30</b>. Alternatively, the product engagement member <b>105</b> may be actively moved by, for example, an actuator, so that its movement to the home position is not obstructed by the product <b>45</b>.

To further facilitate and enhance continuous, automated running of the invention product processing system, the product is preferably supplied to the input section <b>25</b> from a stacked input. <figref idref="DRAWINGS">FIG. 6</figref> illustrates a specific embodiment of a vertically extending stacker <b>400</b>, in the form of a chute the walls of which are defined by columns of rollers <b>410</b>. The lower end of the chute is immediately above, and opens onto, the input section <b>25</b>. The upper end of the chute extends above and angles away from the input section. The chute defines a gravity-drop passage in which a plurality of the products can be stacked one on top of the other for successive and automatic loading onto the input section <b>25</b>. After each previous, underlying product has landed on the input section support bars and been passed from beneath the chute into the scanning section <b>30</b> by the fingers <b>50</b>, the next product in the stack drops onto the input section support bars such that the system is automatically loaded for a continuous running operation.

As a back-up precaution in the event the scanning section drive <b>350</b> gets ahead of the return movement of the fingers <b>130</b>, there is preferably provided a product stop <b>380</b>, shown in <figref idref="DRAWINGS">FIG. 7</figref>, which could hold the movement of the product under the influence of the engagement member <b>105</b> until the fingers <b>130</b> have fully returned to engage the next product. The product stopper <b>380</b> is freely pivotable about a transverse, horizontal axis, and formed at a forward side with an L-shaped stop wall <b>381</b> and on the other side of the pivot axis with a counterweight abutment <b>382</b>. Until the piston carrying the fingers <b>130</b> is fully returned, the L-shaped stop wall <b>381</b> is in a raised blocking position in the path of conveyance of the next product being delivered to the vision system housing, as shown by the dotted line image in <figref idref="DRAWINGS">FIG. 7</figref>. With the piston in its fully-returned position, the counterweight abutment <b>382</b> is engaged and raised, causing the stop wall <b>381</b> to be lowered and not obstructing the conveyance movement of the next product. In this case, the engagement member <b>105</b> is able to conduct the product over the tilted-down fingers <b>130</b>, as well as the lowered stop wall, and fully into the vision system housing for further conveyance, from behind, by the then raised fingers <b>130</b>.

Other features of the specific embodiment that are shown in <figref idref="DRAWINGS">FIGS. 4 and 5</figref> include reference reflectors <b>375</b>. The reference reflectors <b>375</b> are those referenced above in connection with the operation of the profiling apparatus <b>15</b>.

Numerous modifications may be made to the foregoing system without departing from the basic teachings thereof. Although the present invention has been described in substantial detail with reference to one or more specific embodiments, those of skill in the art will recognize that changes may be made thereto without departing from the scope and spirit of the invention as set forth herein.